oldoneleg

Trek5200, 62cm, all Ultegra

Bike has been at LBS four times for shifting issue (chain won't stay on the 25t gear unless one contnues to push the brake/shift lever to the left). I've had the rear derailleur screws adjusted, the thumbs screw adjusted, the cassette tightened, even had a cable tie placed on the derailleur cable to hold it closer to the chainstay - nothing works.

I have to double and triple shift to get the chain to get on the 25t and then as soon as I release the brake/shift lever it jumps off. The chain grinds all the way up any hill.

I've been told that it may be a problem with the cable anchor on the chainstay.
I've been told that it works great (it does as long as it is on a workstand).
I've been told that I am fingering the brake/shift lever too low (recommend middle of the brake/shift lever?)

As soon as any riding pressure is applied the shifting problem returns.

Streched cable?

Do these symptoms ring familiar to any of you and/or do you have any suggestions.

As I live in Alexandria VA, I am looking for a great mechanic too.

sydney

No one suggested a hosed shifter.....? If everything else is right including hanger alignment,there isn't much else.One assumes derailer adjustment is right, but that might be a real reach for some nose pickers.Want a really good mechanic?? Buy a Zinn maitenance book and then get real familiar wiht the repair section at www.parktool.com Items 1 and 3 that 'you have been told' sound like BS.Maybe you need another bike shop.

merlinextraligh

is the derailleur hanger bent? Does it do this in the small chainring?

EURO

If it still doesn't stay there when the limit screw on the mech is completely loose, and if it's worse when you are on the bike, I'd say it could well be an out-of alignment frame or a bent mech hanger.

timmhaan

i have the exact same issue with my bike equipped with brand new ultregra 10spd.

the limit screws work great for dialing in the smaller cog, there is more than enough adjustment. the larger cog is a different story. i can get it shifting nearly perfectly on the trainer, but out on the road it always slips between the two largest cogs on the back after several miles of riding.

a couple of forum members were helping me with a flat on a group ride and and they thought my chain was too loose. recommended that i take out a couple of links. would that help with shifting??

sydney

Damm,but that chain in the spokes hurts even from here.

oldoneleg

One time this happened, the chain was frozen in the low gears and wouldn't shift onto any of the highest gears. This happened right by a LBS. They popped it up on a workstand and couldn't get it to shift. It only worked if they manually pulled on the cable. They squirted a bunch of lube in the shifter and then told me I would have to leave the bike. Being 15 miles from home, I figured this was a long walk in cleats and opted to ride the damaged bike home. One mile later it unfroze. This hasn't happened since, but the other shifting issues persist.

Thanks for your reply

sydney

You don't randomly take links out of a chain. There is a methodology to determining if a chain is too long and another for correctly sizing a chain...repair section at www.parktool.com is a big help.They also cover derailer adjustment and many times the final slight adjustment has to be done under riding conditions. Don't live and die by what happens on the stand.

biker7

1. remove your chain.
2. detach the cable from the pinch bolt of the rear derailleur.
3. loosen your stop for the biggest cog all the way.
4. by hand traverse the derailleur all the way through its travel and see if the
derailleur will travel all the way into the spokes unabated. If you get clean
actuation right past the biggest cog, then likely your derailleur is fine.
5. with the cable removed, align the derailleur cage cog and large cassette cog and adjust the stop screw.

6. Reattach the chain.

Before you reattach the cable, click the RH brifter through its cable travel and see if the cable pulls smoothly both out and in.

7. Reattach the cable only this time...reattach it 1/8- 1/4" tighter then the previous position shown where the cable was pinched by the pinch bolt. Disregard that you won't be able to get into your smallest cogs...not the objective. Ride the bike and see if you can hold onto the big cog with the shifter rachet in a different position while under load. If you can, then likely you have a shifter issue or you didn't have enough cable tension to begin with to hold all the way against the stop in the big cog. You may have a shifter issue anyway, but logic suggests if you hold your other cogs ok in their respective rachet positions, then a lower shifter rachet position on the big cog should work.
HTH,
George

biker7

If they squirted a bunch of lube into your shifter mechanism then that can cause the ratchet to slip.
Shifter ratchets work by friction....they are not meant to be lubricated. The shifter may have been hosed anyway so no big deal...but would explain your shifter slipping in the biggest cog.
George

oldoneleg

It does it from the small chain ring, I'll have to check the hanger. Never crashed the bike on that side.

oldoneleg

Thanks for the advice, I'll have a go at it and see what happens

sydney

Nonsense...Shimano shifters come packed with grease, and even the campy ratchet can function with lube, cuz it's a ratchet which you should check websters for the daffynition of. freewheels and freehubs also have ratchets in them that swim in lube.

biker7

You are comparing shifters with freewheels?...ratchets with pawls?...lol.
Better...check your "daffynitions" and the best type of lubrication for each application...they are not the same.
George

mscycler

Daffy Duck has some wacky shifter problems too...I wonder when Mickey has some shifter problems if we can go check websters for mickeynitions and get to the bottom of this.

mscycler

sydney

^^^....What do you think is actually in a shifter genius? I've actually had them apart...Have you? The drill with shimanos like he has when they get cranky and crudded up is to hose them out with a solvent and relube with a spray lube! And, last time I checked a ratchet(your term) needs a pawl to hold it not friction.

USAZorro

Sounds like it could be a stretched cable. Don't know if/how different those newfangled indexed shifters work, but with an old-school set-up I'd put the bike in highest gear, unclamp the derailleur cable, pull out any slack, and then re-clamp the derailleur cable firmly. If that doesn't solve it, you could have frame or mech alignment problems, or possibly too slack a chain.

Zouf

Gawd, oh gawd...

We're talking brifter here, not friction shifter...

biker7

Really? If you cake too much grease in there the rachet may not catch...same with a freehub.
George

sydney

^^^...No, you don't understand, Genius Georgie insist that a ratchet and pawl mechanism does indeed work on FRICTION.

sydney

Give it up
Georgie give it up.You were wrong about the friction BS.....Too much of a heavy lube could hose the works,because it's too stift to allow the pawls and springs to work. A spray lube is not an STI shifter killer.

biker7

syndey...if you inject a contaminated brifter..one full of dirt...with grease it can keep the ratchet from catching.
George

sydney

Besides having fallen off the wagon again, you are making the assumption the lube mentioned was grease. And what happend to that friction BS? Realize how bad it stunk and covered it up??

biker7

Some greases do stink. Branford for example recommends a light synthetic grease for Campy ergo levers which they also suggest for freehubs and packing Campy hubs. It has no where near the viscosity of say heavy automotive grease that can also be injected. As to falling off the wagon...you are just too easy a mark. Know what's worse?...you never being on the wagon.
George

USAZorro

Hey. Why don't yuz guyz take your beef outside?